Is Mounjaro or Wegovy better for weight loss?

Mounjaro isn't FDA-approved for weight loss — its weight-approved sibling is Zepbound (same molecule, tirzepatide). In a 2025 head-to-head (SURMOUNT-5), tirzepatide (Zepbound) produced more average weight loss than semaglutide (Wegovy). The right option is individualized — talk to your clinician.

Are Mounjaro and Wegovy the same kind of drug?

They're both once-weekly injections in the GLP-1 family, but different molecules: Mounjaro is tirzepatide (a dual GIP + GLP-1 agonist) and Wegovy is semaglutide (a GLP-1 agonist). They also have different FDA-approved uses (diabetes vs weight management).

Mounjaro vs Wegovy

By the pharmaranks editorial teamReviewed against FDA prescribing information (DailyMed) + pivotal trials (PubMed) sourcesUpdated Jul 3, 2026How we research

Different drugs with different approved uses: Mounjaro is tirzepatide for type 2 diabetes; Wegovy is semaglutide for chronic weight management. For a like-for-like weight comparison, the matching brands are Zepbound (tirzepatide) vs Wegovy.

At a glance

Attribute	Mounjaro	Wegovy
Active drug	tirzepatide	semaglutide
Drug class	Dual GIP + GLP-1 receptor agonist	GLP-1 receptor agonist
FDA-approved for	Type 2 diabetes	Chronic weight management
How it's taken	Once-weekly injection	Once-weekly injection or once-daily tablet
Maker	Eli Lilly	Novo Nordisk

Mounjarorating & safety →·Wegovyrating & safety →

The short version

Mounjaro and Wegovy are different medicines approved for different things. Mounjaro (tirzepatide, Eli Lilly) is a dual GIP + GLP-1 injection approved for type 2 diabetes; Wegovy (semaglutide, Novo Nordisk) is a GLP-1 injection approved for chronic weight management. So comparing them directly mixes a diabetes brand with a weight brand.

The key difference

If your real question is weight loss, the apples-to-apples comparison is Zepbound (the tirzepatide weight brand) vs Wegovy — and in a 2025 head-to-head (SURMOUNT-5) tirzepatide produced greater average weight loss than semaglutide. Mounjaro itself is not FDA-approved for weight loss; it's the diabetes brand of the same molecule as Zepbound.

What the trials showed on weight

In weight-management trials, tirzepatide averaged about 20% body-weight reduction (SURMOUNT-1, 15 mg) versus about 15% for semaglutide (STEP 1), and outperformed it head-to-head (SURMOUNT-5). But those trials used the weight brands (Zepbound and Wegovy). These are trial averages, not promises — individual results and tolerability vary. This is general information, not medical advice.

Bottom line

Mounjaro (diabetes) and Wegovy (weight) aren't a clean head-to-head. For weight loss, compare Zepbound vs Wegovy; for diabetes, Mounjaro vs Ozempic. The tirzepatide molecule tends to produce more average weight loss, but the right choice depends on your diagnosis, response, side effects, and cost. Not medical advice.

Frequently asked

Is Mounjaro or Wegovy better for weight loss?: Mounjaro isn't FDA-approved for weight loss — its weight-approved sibling is Zepbound (same molecule, tirzepatide). In a 2025 head-to-head (SURMOUNT-5), tirzepatide (Zepbound) produced more average weight loss than semaglutide (Wegovy). The right option is individualized — talk to your clinician.
Are Mounjaro and Wegovy the same kind of drug?: They're both once-weekly injections in the GLP-1 family, but different molecules: Mounjaro is tirzepatide (a dual GIP + GLP-1 agonist) and Wegovy is semaglutide (a GLP-1 agonist). They also have different FDA-approved uses (diabetes vs weight management).

Compare more GLP-1 options

Wegovy vs Ozempic Mounjaro vs Ozempic Zepbound vs Wegovy Zepbound vs Mounjaro Rybelsus vs Ozempic All GLP-1 drugs compared →

Sources

General information, not medical advice, and not a substitute for your clinician. Efficacy figures are pivotal-trial averages — individual results, side effects, and cost vary. Only a licensed healthcare professional can choose, start, switch, or dose these medicines.